Finding the Fourth Proportional to 105.59, 145.62 and 72.32

Step by Step Solution

1. Step 1: Write the proportion equation
   105.59 : 145.62 = 72.32 : x
2. Step 2: Convert to fraction form
   105.59/145.62 = 72.32/x
3. Step 3: Cross multiply
   105.59x = 145.62 × 72.32
4. Step 4: Simplify right side
   105.59x = 10,531.24
5. Step 5: Solve for x
   x = 10,531.24/105.59
6. Step 6: Final answer
   x = 99.74